You miss my point. I have never seen a target which has passed the Leonard test. Not to demonstrate a fault or to demonstrate correct focus. Failing to acknowledge repeatable focus errors due to every attempted target in 162 posts being 'unreliable' is nonsense when no one has used or posted results which show focus consistently works on a reliable target. According to Leonard there has never been a reliable target!

I will play along with your car analogy. In the UK we need to take our car to a garage every year to have it tested for safety (MOT test). Many, many cars fail the test as the owners are not aware of problems that exist with their vehicles. They do not check or inspect their vehicles in sufficient detail to know the problem exists.

There are also manufacturer recalls for faults identified by a few drivers, faults which other drivers may be unaware of.

I hate analogies as they are always tenuous, but the above would seem to be the opposite of what you appear to be using the car analogy to say.

Personally my D800 will focus well in good light with all focus points but is much more erratic in low light than my D3S ever was, exhibiting micro hunting when in AF-c and also much less tolerance to less than perfect focus targets. I have tried a couple of other D800 bodies which acted exactly the same. I need the resolution the camera offers for my architectural clients and can live with the problem. I will, however, comment that the problem exists when a thread such as this arises.

I do agree that starting multiple threads to discuss the same problem is somewhat excessive. If I could not live with the issue I would return the camera to Nikon. If Nikon did not fix the issue I would change brands.

Talking of returning cameras to Nikon, have you any feedback on the AF Assist issue with speedlights? That certainly does seem to be something that Nikon should be able to correct and I'm with you on your approach to Nikon to try and resolve it (having raised a query also).--Have FunPhoto Pete

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